Northern California’s strongest earthquake in the region since 1940 struck a rural part of Mendocino County on Wednesday morning, leaving some people injured but producing no immediate indications of major destruction, authorities said.
The U.S. Geological Survey gave the quake a preliminary magnitude of 5.6, though it was initially reported at a higher magnitude before being revised. It hit at 8:10 a.m. PT about 7 miles northwest of Willits, an agricultural community, at a depth of roughly 5 miles. Shaking was felt across a broad area, including Fort Bragg on the coast, about 50 miles west of the inland epicenter.
The affected part of Mendocino County, an area of small farming towns, lies about 140 miles northeast of San Francisco.
There was no tsunami threat following the quake, and local and state agencies began checking roads, buildings and utilities for damage as the morning unfolded.
Mendocino County spokesperson Heather Rose said hospitals had reported injuries, though she did not have information about how serious they were or what kinds of injuries people suffered. She said county officials were expected to meet later Wednesday, when additional details might be made public.
In a statement, the Mendocino County Executive Office said power outages were affecting more than 6,000 people in six communities near the epicenter. Officials also urged residents to avoid highways and local roads so crews could check for damage and carry out repairs.
Lucy Jones, a longtime California seismologist, said the quake was the largest to hit that area in almost 90 years. Although earthquakes do occur there, she said the region is not located on a major fault.
“The area is not without earthquakes, but they’re usually smaller than this,” Jones said. She added that aftershocks are likely, but they’ll “probably stay on the low side.”
Within an hour of the main shock, three additional quakes measuring less than magnitude 2.7 were recorded near the same area.
At Club Calpella Restaurant, workers had only just opened for the day when the shaking began. Brie Leon said plates and liquor bottles started rattling inside the building.
“I had just turned the open sign on and went back into the kitchen, and that’s when it happened,” she said. “It almost felt like something hit the building.”
Calpella is about 10 miles south of the epicenter, in a part of Mendocino County that has already seen smaller earthquakes this year.
Leon said the shaking sent picture frames off the walls and knocked bottles from shelves in both the restaurant and the adjacent stockroom. Shortly afterward, she and other servers were cleaning up so they could still serve breakfast customers.
“It wasn’t a big, big quake, but things went everywhere,” she said.
Farther away in Kelseyville, about 40 miles southeast of the epicenter, Alan Harris said he and his family were at home when he got an earthquake alert on his cellphone. Moments later, the house started moving.
“I yelled downstairs immediately to my wife and daughter to make sure they were hanging on,” Harris said. “It was scary. You could hear things crashing, mostly on the third floor of the house.”
A security camera inside the home shook sharply during the tremor. On the video, several loud crashing noises can be heard before Harris shouts, “Is everyone OK?”
Harris said the quake lasted around 30 seconds. It knocked framed photographs from the walls and tipped over a computer monitor, but he said the home did not appear to suffer serious damage and he saw no structural problems.
The California Governor’s Office of Emergency Services said nearly 657,000 earthquake early warnings were issued through the MyShake app across Northern California. The agency said it had not received reports of damage or injuries, but was working with local officials to assess the effects of the quake.